THE EVOLUTION LIST

THE EVOLUTION LIST is a forum for commentary, discussion, essays, news, and reviews that illuminate the theory of evolution and its implications in original and insightful ways. Unless otherwise noted, all materials may be quoted or re-published in full, with attribution to the author and THE EVOLUTION LIST. The views expressed herein do not necessarily reflect those of Cornell University, its administration, faculty, students, or staff.

In Plato's dialogue, the Athenian character warns against those natural philosophers who teach that the ultimate elements in the universe and the heavenly bodies were brought into being not by divine intelligence or art but by natural necessity and chance. These natural philosophers teach that the gods and the moral laws attributed to the gods are human inventions. This scientific naturalism appeared to subvert the religious order by teaching atheism. It appeared to subvert the moral order by teaching moral relativism. And it appeared to subvert the political order by depriving the laws of their religious and moral sanction. Plato's Athenian character responds to this threat by developing the reasoning for the intelligent design position as based on four kinds of arguments: a scientific argument, a religious argument, a moral argument, and a political argument.

His scientific argument is that the complex, functional order of the cosmos shows an intentional design by an intelligent agent that cannot be explained through the unintelligent causes of random contingency and natural necessity. His religious argument is that this intelligent designer must be a disembodied intelligence, which is God. His moral argument is that this divine designer is a moral lawgiver who supports human morality. His political argument is that to protect the political order against scientific atheism and immorality, lawgivers must promote the teaching of intelligent design as the alternative to scientific naturalism. Two thousand years later, William Jennings Bryan developed these same four arguments for intelligent design as superior to Darwinian naturalism. Recent intelligent design proponents such as Phillip Johnson, Michael Behe, and Bill Dembski have elaborated these same four arguments.

To Plato, the world of nature that we can perceive with our senses is not “reality” at all. Instead, the truest reality can only be found in what Plato called “ideal forms.” These were essentially ideas or concepts that were related to actual, natural objects, but existed in the mind rather than in nature. Who's mind? To Plato, the ideal forms ultimately existed in the mind of a supernatural entity or entities, which he often equated with the Greek gods or with a creator he referred to as the “demiurge”.

Plato's clearest expression of this relationship between natural objects and ideal forms is contained in the Phaedo, which Plato presents as a record of a discussion between Socrates and several of his followers on the day of his execution. In the Phaedo, Socrates (and, by extension, Plato) argues that the natural objects and processes we observe around us are crude reflections of an underlying ideal reality, one that does not exist in the natural world. He argues that most people perceive these ideal forms dimly if at all. However, philosophers should dedicate their lives to identifying these ideal forms or “essences”, and demonstrating their reality to others.

This philosophical worldview has been called essentialism, because it emphasizes the “essences” of things, rather than their differences. Central to this worldview is the idea that such “essences”, including the human soul, are eternal and unchanging. In the Platonic worldview, the most “real” things - the “essences” - cannot be perceived with the senses at all, but only with the mind, imperfect as it might be in any individual person. Whereas, in the worldview of the natural sciences, and especially naturalism, only natural objects and processes that can be either directly sensed or inferred indirectly from sensory observation are assumed to exist - to be “real”.

Notice here, too, the emphasis on the unchanging, eternal quality of the “essences”, as opposed to natural objects and processes. Natural phenomena (i.e. the non-essential) are always changing, but “real” phenomena are not. Here we see the root of the opposition between the evolutionary worldview - one based on continuous change in nature - and the Platonic worldview - one based on unchanging, timeless, and universal “essences”.

The Platonic essentialist worldview largely replaced the earlier Ionian naturalist worldview, partly because of the predominance of Athens and Athenian culture in the ancient Mediterranean world. This replacement had a serious and long-lasting effect on the development of the natural sciences in western culture. This was because Plato didn't restrict his essentialist doctrine to emotional or abstract philosophical ideals as implied in the Phaedo, such as truth, beauty, and the human “soul”. In other dialogues and in his lectures, he applied the concept of “essences” to natural phenomena as well, arguing that all natural phenomena are imperfect representations of “ideal forms” that exist outside of nature. According to Plato, these “ideal forms” are universal and necessarily unchanging and unchangeable.

Plato also argued that the universe formed a complete and harmonious whole, in which any real change could only result in the annihilation of everything. As noted earlier, he also asserted that the ideal forms that participate in this harmony did not arise spontaneously from nature, but rather were originally created by a supernatural entity often translated as the “demiurge”. Plato taught that the demiurge created the universe and the ideal forms with a purpose in mind, and that all things (i.e. all “essences” and their imperfect representations) were therefore the product of a preexisting plan. Finally, Plato argued for the existence of a human soul, which cannot be perceived with the senses at all, but which is the “real essence” of each person.

This is why I have asserted that Darwin's most "dangerous" idea was his recognition of the reality of the variations that exist between individuals in populations. This variation is produced by various genetic processes, including mutation, recombination, and developmental/phenotypic plasticity, and is the source of all evolutionary innovations (i.e. it is the "creative force" in evolution). Natural selection simply weeds out all of the variations that don't work, and preserves the ones that do (which is why Darwin wanted to call this process "natural preservation", but the term "natural selection" had already gotten stuck to the process).

But to Plato (and his most important student, Aristotle) the variations don't matter; it is the "ideal form" of which those variations are only imperfect representations that really matters. That is, the variations aren't "real," and so for almost three centuries they were ignored. Furthermore, since the "ideal forms" are eternal and unchanging, things like species are as well. Indeed, I believe that the concept of biological species can be traced back directly to Plato's "ideal forms," and that this explains much of the resistance to Darwin's theory. In essence, Darwin argued in the Origin of Species that species aren't fixed entities, but rather can change over time. Furthermore, this change is "real," implying that the variant forms upon which such change depends are "real" as well. Darwin doesn't take his ideas to their logical conclusion, however: that "species" are purely figments of the human imagination (especially as trained in Platonic philosophy, as all of us are).

To believe that "species" don't really exist in nature, and that the only "real" entities in biology are individual organisms is pretty radical stuff. Most taxonomists would bristle at the very suggestion. However, this idea has a long and honorable pedigree as well; it is a variety of nominalism, a philosophical position often said to have been founded by William of Ockham (of "Occam's Razor" fame). Nominalism directly challenges the fundamental basis of Platonic philosophy in the same way that darwinism challenges it in biology. In the long run, I believe that the paradigm shift to the darwinian worldview has been and will continue to be the most important one since the founding of Platonic philosophy (and therefore of the dominant position in western philosophy).

Friday, February 24, 2006

Jurassic Beaver-Otter Fossil Shows Diversity of Early Mammals

In the conventional view, the earliest mammals were small, primitive, shrew-like creatures that did not begin to explore the world's varied environments until the dinosaurs died out 65 million years ago. But scientists are reporting today that they have uncovered fossils of a swimming, fish-eating mammal that lived in China fully 164 million years ago, well before it was thought that some mammals could have spent much of their lives in water.

The extinct species appears to have been an amalgam of animals. It had a broad, scaly tail, flat like a beaver's. Its sharp teeth seemed ideal for eating fish, like an otter's. Its likely lifestyle — burrowing in tunnels on shore and dog-paddling in water — reminds scientists of the modern platypus. Its skeleton suggests that it was about 20 inches long, from snout to the tip of its tail, about the length of a small house cat.

The surprising discovery, made in 2004 in the abundant fossil beds of Liaoning Province, China, is being reported in the journal Science by an international team led by Ji Qiang of Nanjing University. In the article, Dr. Ji and other researchers from the Chinese Academy of Geological Sciences in Beijing and the Carnegie Museum of Natural History in Pittsburgh said the fossil skeleton showed that some mammals occupied more diverse ecological niches than had been suspected in the Jurassic Period, an age dominated by dinosaurs.

Thomas Martin, an authority on early mammals at Senckenberg Research Institute in Frankfurt, said the find pushed back "the mammalian conquest of the waters by more than 100 million years" and "impressively contradicts" the conventional view.

"This exciting fossil," he wrote in a commentary accompanying the report, "is a further jigsaw puzzle piece in a series of recent discoveries, demonstrating that the diversity and early evolutionary history of mammals were much more complex than perceived less than a decade ago."

Despite similarities with some modern animals, the Jurassic mammal has no modern descendants and is not related to any existing species. The discoverers have given it the name Castorocauda lutrasimilis, Latin for "beaver-tail" and "similar to an otter".

Zhe-Xi Luo, one of the discoverers and the curator of vertebrate paleontology at the Carnegie museum, said the specimen was well preserved, unlike the surviving fragments of bone and tooth of most mammals from the dinosaur age. The skeleton is accompanied by fur and scale imprints and the suggestion of soft-tissue webbing in the hind limbs. Dr. Luo said the fur was to keep water from the animal's skin. It is the most primitive known mammal to be preserved with hair, evidence for its evolution before the appearance of more complex mammals. The scientists said the tail and limbs of the newfound specimen were well developed for aquatic life. They surmised that like the platypus, Castorocauda swam in rivers and lakes, ate aquatic animals and insects and built nests in burrows along the shore. The animal had molars specialized for feeding on small fish and small aquatic invertebrates.

"So far, it is the only semiaquatic mammal from the Jurassic," Dr. Luo said.

The skeleton was found by peasants in Liaoning, the province in northeast China that in recent years has produced several notable discoveries of mammal diversity. The semiaquatic mammal was uncovered in the same hilly country where paleontologists have collected fossils of feathered dinosaurs and two 130-million-year-old animals that did not fit the lowly image of mammals of that period. One of them, the size of an opossum, had feasted on a small dinosaur just before dying.

Jin Meng of the American Museum of Natural History in Manhattan, one of the discoverers of previous Liaoning mammals but who was not involved in the most recent one, said in a telephone interview that more than a dozen new mammals from that area had recently produced "real evidence to show the diversity of lifestyles and behaviors of mammals" in the age of dinosaurs.

"We have been seeing mammals at that time that were larger than a mouse or rat, some that climbed trees, and now we see some that could swim in water," Dr. Meng said.

In the outdated phylogeny of eukaryotic evolution that I was taught in high school, mammals were supposed to have diverged from the reptiles at about the same time as the birds – that is, at around the time of the extinction of the dinosaurs near the end of the Cretaceous period (~ 65 million years ago). What I didn't know then was that this picture of the linear evolution of tetrapod vertebrates – from amphibians to reptiles to birds and mammals – was entirely erroneous.

Instead, the evolution of tetrapod vertebrates looks like a bush, with amphibians and the so-called "stem reptiles" diverging in the late Paleozoic (about 250 million years ago), and ancestral mammal-like therapsids radiating during the Triassic and Jurassic periods. As the article implies, these early mammals lived alongside the much larger dinosaurs throughout the entire Mesozoic era (i.e. the "Age of Dinosaurs"). The distribution of the fossils of these Mesozoic mammals indicates that they tended to exploit habitats that reptiles don't: places and times where endothermy (generating your own body heat and retaining it with insulating hair and fur) gave the mammals an advantage over their ectothermic reptilian cousins, such as higher latitudes, elevations, and at night (i.e. nocturnality).

With the extinction of the dinosaurs following the K-T asteroid collision, the mammals radiated widely, essentially filling the ecological niches left vacant by the missing dinosaurs. This radiation, which is often emphasized in accounts of the evolution of mammals, was not the first adaptive radiation of mammals, however. As this fossil discovery indicates, there was a much earlier adaptive radiation of ancient mammals during the early Mesozoic, into ecological niches now filled by such mammals as the platypus, beaver, and otter. It's interesting to note in this context that there appear to have been relatively few small archosaurs that were adapted to the kind of habitats in which these mammals (and their Mesozoic equivalents) lived. The only exceptions were/are the crocodilians. However, nearly all fossil crocodillians from the Mesozoic era are much larger than living forms (such as Florida alligators and crocodiles), and the biogeographic ranges of the living species do not widely overlap. Beavers and otters, in particular, are rarely found in the same streams and rivers as alligators and crocodiles, and vice versa.

So, this new discovery of a Mesozoic beaver-otter doesn't contradict the emerging picture of mammalian evolution. Rather, it adds depth and detail to the story of the adaptive radiations of the mammal-like tetrapods, and integrates that story into the developing chronology of historical geology/climatology and evolutionary biogeography now being elaborated by geologists, paleontologists, and evolutionary biologists.

Thursday, February 23, 2006

Incommensurate Worldviews

I am beginning to understand more about the differences between the physical sciences (such as astronomy, chemistry, and physics) and the biological sciences, and why the worldview of a physical scientist with a strongly mathematical predilection is apparently so different from mine and that of most other biologists (at least, of those biologists of whom I have personal and/or reputable knowledge). Furthermore, it seems to me that these differences are central to the apparent inability of non-biologists to fully comprehend the "darwinian" worldview upon which much of biology (and all of evolutionary theory) has been constructed (and vice versa, of course).

To me, these appear to be the basic differences that inform our worldviews:

1) CONTINGENCY: The biological sciences (i.e. anatomy & physiology, parts of biochemistry, botany, development & embryology, ecology, ethology, evolution, genetics, marine biology, neurobiology, and the allied subdisciplines), like the "earth sciences" (i.e. atmospheric sciences, geology, etc.) are both contingent and historical. That is, they cannot be derived from "first principles" in the way that algebra, calculus, geometry (both euclidean and non-euclidean), probability, symbolic logic, topology, trigonometry, and other "non-empirical" sciences can be. As both Ernst Mayr and Karl Popper have pointed out, historical contingency is inextricably intertwined with biological causation, in a way that it is not in mathematics and the physical sciences. This would appear to be true, by the way, for both "darwinist" and ID models of biological evolution and the fields derived from them. Indeed, even the Judeo-Christian-Muslim worldview is contingent and historical, in ways antithetical to both mathematics and pre-"big bang" cosmological physics.

2) UNIVERSALITY: The biological sciences are also not "universal" in the way that chemistry and physics are. We assume that the processes described by physical "laws" are universal and ahistorical. that is, we assume that they are the same regardless of where, when, and by whom they are investigated. Furthermore, it is tacitly assumed by physical scientists that the "laws" they discover apply everywhere and everywhen, without empirical verification that this is, in fact, the case. It seems to me that this assumption is reinforced by the mathematical precision with which physical processes can be analyzed and described.

By contrast, the entities and processes studied by biologists are necessarily "messy" and often "non-quantifiable," in the sense that they cannot be entirely reduced to purely mathematical abstractions. The great beauty and elegance of Newton's physics and Pauling's chemistry are that the objects and processes they describe can be so reduced, and when they are, they reveal an underlying mathematical regularity, a regularity so precise and so elegant that one is tempted to believe that the mathematical formalism is what is "real" and the physical entities and processes that they describe are, at best, somewhat imperfect expressions of the underlying perfect regularities.

To me, however, what has always been appealing about biology is its very "messiness." As the so-called Law of Experimental Psychology states "Under carefully controlled conditions, the organism does whatever it damn well pleases." Biological entities and processes are not quantifiable in the same way that physical ones are. This is probably due to the immensely greater complexity of biological entities and processes, in which causal mechanisms are tangled and often auto-catalytic.

3) STOCHASTICITY: The biological sciences are irreducibly statistical/stochastic, in ways that neither the physical nor mathematical sciences generally are (although they are becoming moreso as they intrude deeper into biology). R. A. Fisher was not only the premier mathematical modeler of evolution, he was also the founder of modern statistical biometry. This is no accident: both field and laboratory biology (but not 19th century natural history) depend almost completely on statistical analysis. Again, this is probably because the underlying causes for biological processes are so multifarious and intertwined.

Physicists, chemists, and astronomers can accept hypotheses at confidence levels that biologists can never aspire to. Indeed, until recently the whole idea of "confidence levels" was generally outside the vocabulary of the physical sciences. When you repeatedly drop a rock and measure its acceleration, the measurements you get are so precise and fit so well with Newton's descriptive formalism that the idea that one would necessarily need to statistically verify that they do not depart significantly from predictions derived from that formalism seems superfluous. Slight deviations from the predicted behavior of non-living falling objects are considered to be just that: deviations (and most likely the result of observer error, rather than actual deviant causation). Rarely does any physical scientist look at such deviations as indicative of some new, perhaps deeper formalism (but consider, of course, Einstein's explanation of the precession of the orbit of Mercury, which did not fit Newton's predictions).

4) FORMALIZATION: There are many processes in biology, and especially in organismal (i.e. "skin out" biology) that are so resistant to quantification or mathematical formalization that there is the nagging suspicion that they cannot in principle be so quantified or formalized. It is, of course, logically impossible to "prove" a negative assertion like this - after all, our inability to produce a Seldonian "psychohistory" that perfectly formalizes and therefore predicts animal (and human) behavior could simply be the result of a deficiency in our mathematics or our ability to measure and separately analyze all causative factors.

However, my own experience as a field and laboratory biologist (I used to study field voles - Microtus pennsylvanicus - and now I study people) has instilled in me what could be called "Haldane's Suspicion:" that biology "is not only queerer than we imagine, but queerer than we can imagine." That is, given the complexity and interlocking nature of biological causation, it may be literally impossible to convert biology into a mathematically formal science like astronomy, chemistry, or physics.

But that's one of the main reasons I love biology so much. Mathematical formalisms, to me, may be elegant, but they are also sterile. The more perfect the formalism, the more boring and unproductive it seems to me. The physicists' quest for a single unifying "law of everything" is apparently very exciting to people who are enamored of mathematical formalism for its own sake. But to me, it is the very multifariousness – one could even say "cussedness" – of biological organisms and processes that makes them interesting to me. That biology may not have a single, mathematical "grand unifying theory" (yes, evolution isn't it ;-)) means to me that there will always be a place for people like me, who marvel at the individuality, peculiarity, and outright weirdness of life and living things.

5) PLATONIC VS. DARWINIAN WORLDVIEWS: It seems to me that many ID theorists come at science from what could be called a "platonic" approach. That is, a philosophical approach that assumes a priori that platonic "ideal forms" exist and are the basis for all natural forms and processes. To a person with this worldview, mathematics are the most "perfect" of the sciences, as they literally deal only with platonic ideal forms. Astronomy, chemistry, and physics are only slightly less "prefect," as the objects and processes they describe can be reduced to purely mathematical formalisms (without stochastic elements, at least at the macroscopic level), and when they are so reduced, the predictive precision of such formalisms increases, rather than decreases.

By contrast, I come at science from what could be called a "darwinian" approach. Darwin's most revolutionary (and subversive) idea was not natural selection. Indeed, the idea had already been suggested by Edward Blythe. Rather, Darwin's most "dangerous" idea was that the variations between individual organisms (and, by extension, between different biological events) were irreducibly "real." As Ernst Mayr has pointed out, this kind of "population thinking" fundamentally violates platonic idealism, and therefore represents a revolutionary break with mainstream western philosophical traditions.

I am and have always been partial to the "individualist" philosophical stance represented by darwinian variation. It informs everything I think about reality, from the idea that every individual living organism is irreducibly unique to the idea that my life (and, by extension, everybody else's) is irreducibly unique (and non-replicible). Such a philosophical position might seem to lead to a kind of radical "loneliness," and indeed there have been times when that was the case for me. But since all of us are equal in our "aloneness," it paradoxically becomes one of the things we universally share.

And so, I don't think a "darwinian worldview" applies to the physical sciences (and certainly does not apply to non-empirical sciences, such as mathematics), for the reasons I have detailed above. In particular, it seems clear to me that although it may be possible to mathematically model microevolutionary processes (as R. A. Fisher and J. B. S. Haldane first did back in the early 20th century), it is almost certainly impossible to mathematically model macroevolutionary processes. The reason for this impossibility is that macroevolutionary processes are necessarily contingent on non-repeatable (i.e. "historical") events, such as asteroid collisions, volcanic eruptions, sea level alterations, and other large-scale ecological changes, plus the occurrence (or non-occurrence) of particular (and especially major) genetic changes in evolving phylogenies. While it may be possible to model what happens after such an event (e.g. adaptive radiation), the interactions between events such as these are fundamentally unpredictable, and therefore cannot be incorporated in prospective mathematical models of macroevolutionary changes.

It's like that famous cartoon by Sidney Harris: "Then a miracle occurs..." The kinds of events that are often correlated with major macroevolutionary changes (such as mass extinctions and subsequent adaptive radiations) are like miracles, in that they are unpredictable and unrepeatable, and therefore can't be integrated into mathematical models that require monotonically changing dynamical systems (like newtonian mechanics, for example).

So, to sum up, I believe that the "darwinian worldview" applies only to those natural sciences that are both contingent and intrinsically historical, such as biology, geology, and parts of astrophysics/cosmology. Does this make such sciences less "valid" than the non-historical (i.e. physical) sciences? Not at all; given that physical laws now appear to critically depend on historical/unrepeatable events such as the "big bang," it may turn out to be the other way around. In the long run, even the physical sciences may have to be reinterpreted as depending on contingent/historical events, leaving the non-empirical sciences (mathematics and metaphysics) as the only "universal" (i.e. non-contingent/ahistorical) sciences.

P.S. Alert readers may recognize some of the hallmarks of the so-called Apollonian vs. Dionysian dichotomy in the preceding analysis. That such characteristics are recognizable in my analysis is not necessarily an accident.

P.P.S. It is also very important to keep in mind, when considering any analysis of this sort, that sweeping generalizations are always wrong ;-)

Saturday, February 18, 2006

There's Something Fishy About Human Brain Evolution

Forget the textbook story about tool use and language sparking the dramatic evolutionary growth of the human brain. Instead, imagine ancient hominid children chasing frogs. Not for fun, but for food.

According to Dr. Stephen Cunnane it was a rich and secure shore-based diet that fueled and provided the essential nutrients to make our brains what they are today. Controversially, according to Dr. Cunnane our initial brain boost didn't happen by adaptation, but by exaptation, or chance.

"Anthropologists and evolutionary biologists usually point to things like the rise of language and tool making to explain the massive expansion of early hominid brains. But this is a Catch-22. Something had to start the process of brain expansion and I think it was early humans eating clams, frogs, bird eggs and fish from shoreline environments. This is what created the necessary physiological conditions for explosive brain growth," says Dr. Cunnane, a metabolic physiologist at the University of Sherbrooke in Sherbrooke, Quebec.

The evolutionary growth in hominid brain size remains a mystery and a major point of contention among anthropologists. Our brains weigh roughly twice as much as our similarly sized earliest human relative, Homo habilis two million years ago. The big question is which came first – the bigger brain or the social, linguistic and tool-making skills we associate with it?

But, Dr. Cunnane argues that most anthropologists are ignorant or dismissive of the key missing link to help answer this question: the metabolic constraints that are critical for healthy human brain development today, and for its evolution.

Human brains aren't just comparatively big, they're hungry. The average newborn's brain consumes an amazing 75-per cent of an infant's daily energy needs. According to Dr. Cunnane, to fuel this neural demand, human babies are born with a built-in energy reservoir – that cute baby fat. Human infants are the only primate babies born with excess fat. It accounts for about 14 per cent of their birth weight, similar to that of their brains.

It's this baby fat, says Dr. Cunnane, that provided the physiological winning conditions for hominids' evolutionary brain expansion. And how were hominid babies able to pack on the extra pounds? According to Cunnane their moms were dining on shoreline delicacies like clams and catfish.

"The shores gave us food security and higher nutrient density. My hypothesis is that to permit the brain to start to increase in size, the fittest early humans were those with the fattest infants," says Dr. Cunnane, author of the book Survival of the Fattest, published in 2005.

Unlike the prehistoric savannahs or forests, argues Dr. Cunnane, ancient shoreline environments provided a year-round, accessible and rich food supply. Such an environment was found in the wetlands and river and lake shorelines that dominated east Africa's prehistoric Rift Valley in which early humans evolved.

Dr. Cunnane points to the table scrap fossil evidence collected by his symposium co-organizer Dr. Kathy Stewart from the Canadian Museum of Nature, in Ottawa. Her study of fossil material excavated from numerous Homo habilis sites in eastern Africa revealed a bevy of chewed fish bones, particularly catfish.

More than just filling the larder, shorelines provided essential brain boosting nutrients and minerals that launched Homo sapiens brains past their primate peers, says Dr. Cunnane, the Canada Research Chair in Brain Metabolism and Aging.

Brain development and function requires ample supplies of a particular polyunsaturated fatty acid: docosahexaenoic acid (DHA). DHA is critical to proper neuron function. Human baby fat provides both an energy source for the rapidly growing infant grey matter, and also, says Dr. Cunnane, a greater concentration of DHA per pound than at any other time in life.

Aquatic foods are also rich in iodine, a key brain nutrient. Iodine is present in much lower amounts from terrestrial food sources such as mammals and plants.

It was this combination of abundant shoreline food and the "brain selective nutrients" that sparked the growth of the human brain, he says.

"Initially there wasn't selection for a larger brain," argues Dr. Cunnane. "The genetic possibility was there, but it remained silent until it was catalyzed by this shore-based diet."

Dr. Cunnane acknowledges that for the past 20 years he's been swimming upstream when it comes to convincing anthropologists of his position, especially that initial hominid brain expansion happened by chance rather than adaptation.

But, he says, the evidence of the importance of key shoreline nutrients to brain development is still with us – painfully so. Iodine deficiency is the world's leading nutrient deficiency. It affects more than a 1.5 billion people, mostly in inland areas, and causes sub-optimal brain function. Iodine is legally required to be added to salt in more than 100 countries.

Several decades ago, Elaine Morgan ignited a controversy among anthropologists and paleontologists by writing The Aquatic Ape and The Descent of Woman, in which she popularized the theories of Sir Alistair Hardy, who proposed that the evolution of humans from our primate ancestors could best be explained by the assumption that seashores, not savannahs, are our "ancestral" habitat. At the time, both Morgan and Hardy were, like Lynn Margulis and Peter Mitchell, considered to be "crackpots" and "nut cases."

However, recent research into human evolutionary biogeography has lent convincing support to the "aquatic ape hypothesis. As you can see in this website, the biogeographical distribution of marker DNA sequences in our phylogenetic clade closely mirrors the archaeological and paleontological evidence for hominin migrations out of east Africa. For over a million years, our ancestors hugged the shorelines of the old and new worlds...indeed, as any glance at a world map shows, we still do.

Friday, February 17, 2006

"The wild geese and every species of water fowl darkened the surface of every bay ... in flocks of millions.... When disturbed, they arose to fly. The sound of their wings was like that of distant thunder." --George Yount, California pioneer, at San Francisco Bay in 1833

When explorers and pioneers visited California in the 1700s and early 1800s, they were astonished by the abundance of birds, elk, deer, marine mammals, and other wildlife they encountered. Since then, people assumed such faunal wealth represented California's natural condition -- a product of Native Americans' living in harmony with the wildlife and the land and used it as the baseline for measuring modern environmental damage.

That assumption now is collapsing because University of Utah archaeologist Jack M. Broughton spent seven years -- from 1997 to 2004 -- painstakingly picking through 5,736 bird bones found in an ancient Native American garbage dump on the shores of San Francisco Bay. He determined the species of every bone, or, when that wasn't possible, at least the family, and used the bones to reconstruct a portrait of human bird-hunting behavior spanning 1,900 years.Broughton concluded that California wasn't always a lush Eden before settlers arrived. Instead, from 2,600 to at least 700 years ago, native people hunted some species to local extinction, and wildlife returned to "fabulous abundances" only after European diseases decimated Indian populations starting in the 1500s.

Broughton's study of bird bones, published in Ornithological Monographs, mirrors earlier research in which he found that fish such as sturgeon, mammals such as elk, and other wildlife also sustained significant population declines at the hands of ancient Indian hunters.

Biologists long assumed that the abundant wildlife in California some 200 years ago had existed for thousands of years -- an assumption "that is ultimately used to make decisions about how to manage and conserve threatened or endangered species," says Broughton, an associate professor of anthropology.

"Since European discovery, California has been viewed by scholars and scientists, as well as the general public -- as a kind of utopia or a land of milk and honey, a super-rich natural environment," he says. "This perception has long colored anthropological research on the state's native peoples. The harvesting methods and strategies of native peoples have been suggested to have promoted the apparent superabundance of wildlife, and have been proposed as models for the management of wilderness areas and national parks today."

Broughton says his study challenges "a common perception about ancient Native Americans as healthy, happy people living in harmony with the environment. That clearly was not always the case. Depending on when and where you look back in time, native peoples were either living in harmony with nature or eating their way through a vast array of large-sized, attractive prey species."

The study may have broader implications. Broughton speculates that "utopian perceptions" of a pristine California teeming with wildlife "probably even influence how Californians view themselves, and how the world views the Golden State. The dream world of Disneyland, the glamor and glimmer of Hollywood, the Baywatch fun-in-the-sun culture -- all of this may trace a link to early historic descriptions of the land that now appear to be worlds apart from pre-European conditions."

Himself a product of sunny California, Broughton grew up in rural Camarillo in the southern part of the state, "collecting butterflies, watching birds, and skinning skunks." While earning bachelor's and master's degrees at California State University, Chico, he studied bones from archaeological sites in California's Sacramento Valley and began to recognize that early natives had a strong impact on elk, deer, and sturgeon -- "anything big and juicy," he says.For his doctoral dissertation at the University of Washington, Broughton analyzed fish and mammal bones taken from the Emeryville shellmound, an ancient Indian site on the east shore of San Francisco Bay between Oakland and Berkeley.

About 2,600 years ago, California's native people started living on the site and using it to dump residential waste such as shellfish remnants, bones, soil, rocks, ash and charcoal, and artifacts such as stone tools. The mound slowly grew until it was more than 30 feet tall, as long as three football fields, and as wide as the length of one football field. Then, in the 1800s, the top layers were flattened to make way for a dance pavilion, eliminating debris from recent centuries. What was left was a record of refuse containing the kinds of things native Californians hunted and ate from 2,600 to 700 years ago.

Emeryville was the largest of some 425 shellmounds identified along San Francisco Bay by 1900. It was made up of distinct layers, which allowed dating of its bones. In 1902, 1906, and 1924, scientists excavated thousands from the shellmound, recording the layer in which each bone was found. The shellmound then was destroyed by a steam shovel to make way for a paint factory, which was razed in the 1990s and replaced by retail stores. The shellmound bones were stored for decades at the Phoebe Apperson Hearst Museum of Anthropology at the University of California, Berkeley.

After finishing his dissertation on Emeryville mammal and fish bones, Broughton joined the University of Utah faculty in 1995. Two years later, he started examining the Hearst Museum's bird bones from the shellmound, alternating between that project and other research during the next seven years.

Analyzing 5,736 bones was a labor of love for him. "It's fun and relaxing," Broughton says. "It's a real challenge when you've got a broken bird bone and it could be any of 100 species. It may take hours or a day to identify a single bone. So you can imagine the excitement when you finally nail it."

To identify the shellmound bones, Broughton painstakingly compared them with bird bones kept in the University of Utah's Zooarchaeology Laboratory, which includes specimens from numerous sources, ranging from road kill to victims of Alaska's Exxon Valdez oil tanker spill.Broughton found that the Hearst Museum's bones represented 64 species: 45 species of waterbirds, including ducks, geese, cormorants, and shorebirds; 15 species of raptors such as red-tailed hawks and bald eagles; and two species each from the groups that include grouse and quail, and crows and ravens. In terms of the number of specimens, waterbirds were most abundant, particularly ducks, geese, and cormorants.

By analyzing the relative abundances of the birds, Broughton showed that the bird population diminished throughout the entire 1,900-year period represented by the shellmound. Species with the most significant population reductions were those most attractive to hunters: large birds and birds that lived closer to humans. Among waterfowl, large geese on land and in marshes declined sooner than smaller geese and ducks, but as the supply of large geese waned, an increasing number of small geese and ducks from estuaries were hunted and their bones dumped in the shellmound.

As nearby food sources diminished, native peoples increasingly hunted birds at greater distances--particularly cormorant chicks on island breeding colonies--and depleted their populations. The bones also show increased hunting over time of sea ducks, found only in open water and on the outer coast, as duck populations lessened on land and in marshes. After depleting larger shorebirds -- marbled godwits, long-billed curlews, and whimbrels -- natives then hunted smaller shorebirds such as sandpipers.

Broughton's conclusion that hunting by native peoples depressed bird populations came only after he rejected possible alternative causes, such as changes in prehistoric climate and reductions in bird habitat. For example, the decline in cormorants might have been caused by the climate disruption known as ElNiño . If true, the species most affected should be Brandt's and pelagic cormorants, which depend on food in ocean currents altered by ElNiño. Instead, the population decline was most pronounced in double-crested cormorants, which lived closer to Indian hunters.

Broughton believes the Bay Area harbored a prehistoric native population of 50,000 to 150,000 before Europeans arrived in the 1500s. He believes that birds and other wildlife rebounded only after early European explorers came into contact with natives, infecting them with fatal diseases such as smallpox, malaria, and influenza and killing off as much as 90 percent of the Indian population. As a result, hunting pressure diminished, and by the mid-1800s, geese and ducks "were so abundant you could kill them with a club or stick," he says.

Until Broughton's study, "the general consensus was that pre-European humans living in North America had little or no effect on continental wildlife populations," says a commentary by John Faaborg, editor of Ornithological Monographs and a wildlife biology professor at the University of Missouri-Columbia. Except for "special cases" of ancient natives decimating bird populations on islands -- such as Hawaii 1,000 years ago -- many scientists view "negative effects on bird populations as a modern phenomenon, one that came along with burgeoning populations virtually throughout the globe," he adds.

But now, Faaborg writes, "We need to reconsider our impressions about human impacts on bird populations in the distant past. Jack Broughton makes an excellent case that native peoples living in the San Francisco Bay area harvested enough birds to deplete populations and even cause some local extinction, perhaps as long as 2,000 years ago."

While bird researchers emphasize human-caused environmental damage when discussing modern loss of birds, they often "do not consider that similar processes may have been occurring for thousands of years," Broughton concludes. Although visitors in the 1700s and early 1800s "witnessed an astonishing abundance of wildlife, the region had been characterized by human-induced faunal poverty only decades before and would nearly return to that condition with the wave of human consumers that came with the Gold Rush.

I was once one of those who believed in the myth of the "noble savages," who had an innate sense of ecological balance and would never act in a way that damaged their environment. As the reference to Rousseau implies, this was indeed a myth, based not on observation nor reality but on philosophical speculation. As recent archaeological and ecological studies have pointed out, the pre-European human populations of North and South America sometimes had severe ecological impacts on their environment. Perhaps the most significant of these was the decimation of the Pleistocene megafauna by the original human migrants from east Asia. As the animations at this website illustrate, there is a direct correlation between the ages of the remains of now-extinct Pleistocene megafauna (horses, camels, ground sloths, and mammoths, among others) and the spread of migrating humans into North America following the opening of the Bering land bridge.

Paul Martin, a professor at the University of Arizona has studied these extinctions for over forth years, and has concluded that humans were largely responsible for the extinctions of many of the species of large mammals and birds noted as having disappeared from the archaeological and paleontological record following the arrival of humans in North America.

More recent studies, such as the one reported in this article, have shown that these extinctions and near-extinctions did not end with the elimination of the North American megafauna. Local and regional extinctions, linked in many cases to human activity, have continued up to the present day throughout the old and new worlds, and especially in the Pacific Islands.

Should we really be surprised at this? I don't think so. Humans are smart, adaptable animals, but in general we have very little foresight. When there were few of us and lots of other animals (and there were many places where few if any people lived), it was quite easy to "live high" for a while on the surplus of the land. When the local animals began to get scarce, our ancestors simply moved on. This pattern of "live it up and leave" existence has been the general rule for most gatherer/hunter societies throughout most of our evolutionary history.

Only recently have we become aware of the downside of this subsistence pattern. This awareness has come, not through philosophical speculation or attention to comforting myths, but rather from the empirical sciences, especially archaeology, paleontology, and ecology (especially paleoecology). It has also come from the simple fact that there is no longer any place to go after we "live it up." When the human population of all of North America was less than the population of North Dakota it was possible to make a good living without making a big killing. We no longer have that option.

Thursday, February 16, 2006

Evolution Measure Splits State Legislators In Utah

SALT LAKE CITY, Feb. 3 ˜ Faith's domain is evident everywhere at the Utah Legislature, where about 90 percent of the elected officials are members of the Church of Jesus Christ of Latter-day Saints. Prayers are commonplace, and lawmakers speak of their relationship with God in ordinary conversation.

So it might be tempting to assume that legislation relating to the divisive national debate about the teaching of evolution in public schools would have a predictable outcome here.

Senate Bill 96 is proving that assumption wrong. The bill, which would require science teachers to offer a disclaimer when introducing lessons on evolution ˜ namely, that not all scientists agree on the origins of life ˜ has deeply divided lawmakers. Some leaders in both parties have announced their opposition to the bill, and most lawmakers say that with less than a month left in the legislative session, its fate remains a tossup.

One of the reasons why is State Representative Stephen H. Urquhart, a Republican from southern Utah whose job as majority whip is to line up votes in his party. Mr. Urquhart announced last week that he would vote against the bill.

"I don't think God has an argument with science," said Mr. Urquhart, who was a biology major in college and now practices law.

Mr. Urquhart says he objects to the bill in part because it raises questions about the validity of evolution, and in part because the measure threatens traditional religious belief by blurring the lines between faith and science.

Supporters of the bill, which passed the Senate on a 16-to-12 vote one day before Mr. Urquhart's announcement, still predict that it will pass in the House. They say the bill is not about religion, but science. Gov. Jon Huntsman Jr., a Republican and former Mormon missionary, has not said what he will do if the bill reaches his desk.

"I don't have to talk about religion ˜ it's of no meaning and it's not part of this discussion," said State Representative James A. Ferrin, a Republican and the sponsor of the bill in the House. "It's not about belief, it's about not overstepping what we know."

Opponents of the bill, including State Senator Peter C. Knudson, the Republican majority leader, openly laugh at talk like that.

"Of course it's about religion," Mr. Knudson said.

He and other lawmakers say that part of the debate here is in fact over what kind of religion would be buttressed by the legislation. Although the Origins of Life bill, as it is formally known, does not mention an alternative theory to evolution, some legislators say they think that voting yes could be tantamount to supporting intelligent design, which posits an undefined intelligence lurking behind the miracles of life and which differs greatly from the Mormon creation story.

"There are people who say, 'That's not my religion,' or that it will only confuse our children," said State Representative Brad King, a Democrat and the minority whip in the House, who also plans to vote against the bill. "For me, it's sort of that way," added Mr. King, whose father, a Mormon bishop, taught evolution at the College of Eastern Utah.

Others say that Mormonism, with its emphasis that all beings can progress toward higher planes of existence, before and after death, has an almost built-in receptivity toward evolutionary thought that other religions might lack. Still others oppose the state's inserting itself in matters of curriculum, which are mostly under the control of local school districts.

Advocacy groups who follow the battle over the teaching of evolution nationally say that what happens here could be important far beyond state borders.

"It's being watched very closely because of the very conservative nature of the state," said the Rev. Barry W. Lynn, the executive director of Americans United for Separation of Church and State, based in Washington. "If the legislation is rejected in Utah, it would be a very strong signal that the issue should be avoided elsewhere."

Missouri's legislature is considering a bill requiring "critical analysis" in teaching evolution. An Indiana lawmaker has called evolution a type of religion and proposed a bill banning textbooks that contain "fraudulent information."

Gov. Ernie Fletcher of Kentucky, a Republican, pointed out in his State of the State address earlier this month that alternative explanations for the origins of species can already be taught in Kentucky schools. A spokesman for Mr. Fletcher said he was not advocating alternatives to evolution, but merely pointing out the options.

The Utah bill's main sponsor, State Senator D. Chris Buttars, a Republican from the Salt Lake City suburbs, said he was not surprised by the debate it had inspired. He said ordinary voters were deeply concerned about the teaching of evolution.

"I got tired of people calling me and saying, 'Why is my kid coming home from high school and saying his biology teacher told him he evolved from a chimpanzee?' " Mr. Buttars said.

Evolutionary theory does not say that humans evolved from chimpanzees or from any existing species, but rather that common ancestors gave rise to multiple species and that natural selection ˜ in which the creatures best adapted to an environment pass their genes to the next generation ˜ was the means by which divergence occurred over time. All modern biology is based on the theory, and within the scientific community, at least, there is no controversy about it.

Even so, one important supporter of the bill, State Representative Margaret Dayton, a Republican and chairwoman of the House Education Committee, said her convictions had been underlined in recent days. "A number of scientists have been in touch with me, and I can verify that not all scientists agree," Ms. Dayton said.

Utah's predominant faith has also made its stance less predictable on other issues touching on religion in school ˜ notably school prayer. Enthusiasm for the idea has been muted or ambivalent, said Kirk Jowers, a professor of political science and director of the Hinckley Institute of Politics at the University of Utah. Professor Jowers pointed to the awareness among Mormons of their religion's minority status in the nation and world.

"It was kind of a realization that if you push to have prayer in school, then outside of Utah, the prayer would not typically be a Mormon's prayer, so is that road you want go down?" Professor Jowers said.

The Utah case is very special, in the same way that Utah is very special: if any state in the US could be considered a “theocracy,” it's Utah. Mormons control the state government and legislature and virtually all other governmental and social institutions. Despite this, they have generally resisted the temptation to intrude religion into politics. Voters in the state are generally quite conservative (voter registration is overwhelmingly Republican), but it would be difficult to pigeonhole them as the kind of conservative that toes the fundamentalist/creationist party line. True, one of their state senators, D. Chris Buttars (Republican) is clearly a creationist, but the Mormon mainstream is definitely not on the side of either creationism or “intelligent design.”

There is also a very deep tradition of self-reliance among Utah folk, which goes along with their conservatism. They don't like outsiders (like the guys in fancy suits from either the Discovery Institute or the National Center for Science Education) telling them what to think. There is also a burgeoning high technology industry in Utah, and much of the younger generation there would probably classify themselves as “sci-tech geeks” (at least the ones I know would). University educated, most of them would prefer that their state and its schools not be classified as favoring “supernaturalism” over science.

Furthermore, as is pointed out in the article, Mormon theology deviates quite substantially from fundamentalist Christianity. As might be expected from the largest and most successful religion founded in 19th century America (in upstate New York, just a short drive from here, no less), Mormonism is both forward-looking and open to “new revelation.” Unlike the fundamentalist creationist Christians, therefore, most Mormons don't necessarily view the Bible (nor the Book of Mormon) as literal truth, nor do they have the innate fear of science and technology shared by most fundamentalists.

And so, Senator Buttars notwithstanding, Utah could go either way in the “evolution wars.” It depends a lot on whether the “know nothing” contingent in the state legislature (led by Buttars) can sway enough of the public to force public opinion over to their side. Given the recent events in Pennsylvania and Ohio (both Christian and Republican strongholds, and both throwing out “intelligent design”), the outcome in Utah is far from a foregone conclusion.

P.S. In the interests of full disclosure, even though I'm related to Brigham Young, I'm not a Mormon. When he was a boy, his family lived only a couple of miles from where my mother's family has lived for generations (my great-great grandmother was a Young).

Tuesday, February 14, 2006

Ohio School Board Votes Down Lesson Plan Criticizing Evolution

It's been a tough couple of months for the promoters and supporters of "intelligent design (ID)." Last December, ID supporters in Dover, Pennsylvania were handed a resounding defeat when Judge John E. Jones ( a conservative Republican Bush appointee) handed down a legal decision blocking the reading of statements supporting ID in Dover high school biology classes.

Now late this afternoon, the Ohio state school board voted 11 to 4 to eliminate eliminate a lesson plan and science standards that supporters of evolutionary theory said opened the door to teaching intelligent design. Specifically, the board voted to delete material in the lesson plan that encouraged students to seek evidence for and against certain aspects of evolutionary biology.

This vote reversed a close 9-8 decision in January to keep the lesson plan. Three of the board members who voted to keep the lesson plan in January were absent from today's deliberations, and have vowed to reinstate the material critical of evolution at an upcoming meeting. However, given the margin of victory today, it is unlikely that they will succeed. The Panda's Thumb has a compendium of information and links spanning this entire controversy.

As I mentioned in an earlier post, the governor of Ohio has recently criticized the lesson plan, saying that he should have exercised more control over the appointment of ID supporters to the state school board, with the clear implication that in the future he would do what he could to prevent ID supporters from influencing state educational policy.

Ohio Citizens for Science has issued a press release applauding the decision, while at the same time calling on supporters of evolution to continue to oppose efforts to insert ID theory into state lesson plans.

You might think that with all of these defeats, the ID movement would re-think its strategy. However, this seems unlikely as all of the recent legal maneuvering has come as the result of the ID movement having already changed their strategy. In 1998, the Discovery Institute, home and principle sponsor of the ID movement, promulgated what has now become known as the "wedge document," in which they laid out a five-year strategy to "defeat scientific materialism" and "replace materialistic explanations with the theistic understanding that nature and human beings are created by God." In it, they stated clearly that their first priority was research, writing and publication: that is, to develop a program of basic science in which ID theory would be tested and presented to the scientific community in such a way as to convince a critical mass of scientists that the theory had merit. As the author(s) of the wedge document stated, "Without solid scholarship, research and argument, the project would be just another attempt to indoctrinate instead of persuade."

Only once ID theory had been established in the scientific community would its supporters attempt to influence educational and public policy:

"Once our research and writing have had time to mature, and the public prepared for the reception of design theory, we will move toward direct confrontation with the advocates of materialist science through challenge conferences in significant academic settings. We will also pursue possible legal assistance in response to resistance to the integration of design theory into public school science curricula. The attention, publicity, and influence of design theory should draw scientific materialists into open debate with design theorists, and we will be ready. With an added emphasis to the social sciences and humanities, we will begin to address the specific social consequences of materialism and the Darwinist theory that supports it in the sciences."

The history of the intervening eight years shows just the opposite: only four articles relating to ID theory have been published in peer-reviewed scientific journals. None of these four articles contains the results of actual empirical (i.e. field or laboratory) tests of predictions formulated using ID theory. A grand total of only 34 articles and books (i.e. approximately four per year) have been produced during that entire time, as compared with thousands of articles and books in the mainstream scientific community on the various aspects of evolutionary theory.

Instead, the ID movement, and especially the Discovery Institute, has moved directly into the public arena, spending nearly all of their energy and financial resources on interventions in school board decisions, political elections, and press releases. Clearly, having lost the battle in the scientific community, they are attempting to appeal directly to the general public, hoping that slick publicity will succeed where scientific research (or rather, the lack thereof) has failed.

If I were a scientist who supported ID theory, or even a scientist who supported the idea of free and unfettered research, I would view the people at the Discovery Institute and their supporters in the various governments and school boards as traitors. The fact that Michael Behe and William Dembski don't see them that way says a lot about their confusion about the difference between science and politics.

Ohio Expected To Rein In Class Linked To Intelligent Design

The legal precedent set by Judge John E. Jones' decision in the Dover case, in which "intelligent design theory" was found to be a religious theory masquerading as science, has now reached to the state of Ohio. Here's today's story in the New York Times (commentary follows):

COLUMBUS, Ohio, Feb. 13 — A majority of members on the Board of Education of Ohio, the first state to single out evolution for "critical analysis" in science classes more than three years ago, are expected on Tuesday to challenge a model biology lesson plan they consider an excuse to teach the tenets of the disputed theory of intelligent design.

A reversal in Ohio would be the most significant in a series of developments signaling a sea change across the country against intelligent design — which posits that life is too complex to be explained by evolution alone — since a federal judge's ruling in December that teaching the theory in the public schools of Dover, Pa., was unconstitutional.

A small rural school district in California last month quickly scuttled plans for a philosophy elective on intelligent design after being challenged by lawyers involved in the Pennsylvania case. Also last month, an Indiana lawmaker who said in November that he would introduce legislation to mandate teaching of intelligent design instead offered a watered-down bill requiring only "accuracy in textbooks." And just last week, two Democrats in Wisconsin proposed a ban on schools' teaching intelligent design as science, the first such proposal in the country.

Here in Ohio, pressure has been mounting on board members in recent weeks to toss out the lesson plan and the standards underpinning it. Gov. Bob Taft, a Republican, called this month for a legal review of the plan, while newly revealed documents of Ohio's Department of Education linking it to treatises of the intelligent design movement have renewed threats of a lawsuit by opponents of the movement.

At the same time, a national group of evolution defenders has bombarded 5 of the 19 board members considered crucial to a vote against the lesson plan with 30,000 e-mail messages over the past week, and just Monday, the president of the National Academy of Sciences urged the board to change the lesson and the underlying curriculum guidelines to "conform to established scientific standards."

"All of that adds up to a sense of urgency and a sense of now is the time to clean up our act," said Robin C. Hovis, a stockbroker from Millersburg who is one of two board members pushing an emergency motion on Tuesday to delete the "critical analysis" language and the lesson plan. "There is an atmosphere among the board, at least a growing atmosphere, that this is a misguided policy and we better get rid of it."

Though the lesson plan is optional and never uses the words "intelligent design," its explanation of concepts like homology, the fossil record and endosymbiosis parallel those in the texts "Icons of Evolution" and "Of Pandas and People," written by proponents of intelligent design.

"All of that adds up to a sense of urgency and a sense of now is the time to clean up our act," said Robin C. Hovis, a stockbroker from Millersburg who is one of two board members pushing an emergency motion on Tuesday to delete the "critical analysis" language and the lesson plan. "There is an atmosphere among the board, at least a growing atmosphere, that this is a misguided policy and we better get rid of it."

Though the lesson plan is optional and never uses the words "intelligent design," its explanation of concepts like homology, the fossil record and endosymbiosis parallel those in the texts "Icons of Evolution" and "Of Pandas and People," written by proponents of intelligent design.

The Discovery Institute, in Seattle, the intellectual home of the design movement, had distanced itself from the Dover case but has long heralded Ohio's "critical analysis" approach as a model for the nation, and is ardently defending the lesson plan.

On Monday, the institute released a Zogby International poll it had commissioned showing that 69 percent of Ohio voters believed that scientific evidence against evolution should be included in curriculums, and 76 percent agreed that "students should also be able to learn about scientific evidence that points to an intelligent design of life." The institute has also proffered letters from two science professors supporting Ohio's standards and model lesson plan.

John G. West, associate director of the Center for Science and Culture at the institute, said: "This just shows the extremism of the other side. They think Dover is their wedge to try to stop any even voluntary critical analysis of Darwin's theory in the classroom. They obviously don't think they can win in the court of public opinion on the issue, and that's why they're using scare tactics."

Local supporters of the standards echoed Mr. West's confidence that, unlike the Dover curriculum, the one in Ohio could pass constitutional muster. The Pennsylvania ruling is not binding elsewhere.

"If I had the money, I'd pay for the lawsuit," said David Zanotti, president of the conservative American Policy Roundtable in Strongsville, Ohio. "They should sue or shut up."

Debate over evolution here dates to 2000, when the board began developing statewide academic standards, which do not dictate curriculum to the 613 local districts but provide a blueprint for standardized tests.

A proposal to teach intelligent design alongside evolution was rejected. Instead, the board in December 2002 unanimously adopted standards requiring that 10th graders be able to "describe how scientists continue to investigate and critically analyze aspects of evolutionary theory," with a parenthetical note that "this benchmark does not mandate the teaching or testing of intelligent design."

Since then, New Mexico, Minnesota and Kansas have adopted similar standards, and Pennsylvania lists evolution among half a dozen theories to be critically analyzed. But only Ohio has a model lesson plan, adopted by a divided board in 2004, that provides teachers a practical how-to guide. It is unclear how frequently it is used.

Besides the Dover decision, the disclosure in December of documents detailing internal discussions of the lesson plan helped revive debate here. Obtained by Americans United for the Separation of Church and State, a group considering a suit on the plan, the documents show that department scientists and outside experts condemned the lesson as "a lie," "crackpot," "religious," "creationism" and "an insult to science."

Asked whether the lesson connects skills to the real world, an external reviewer wrote: "Not the real scientific world. The real religious world, yes, the real world based on faith, yes, the real world of fringe thinking, yes!"

Patricia Princehouse, an evolutionary biologist and historian of science who has led the charge against the lesson plan, said, "Basically critical analysis is intelligent design relabeled, just as intelligent design was creationism relabeled."

Governor Taft entered the fray in early February, telling newspaper reporters and editors that the board should ask the attorney general to review the lesson; that intelligent design should not be taught or tested; and that he should have questioned candidates more vigorously on the issue before filling the eight board seats he controls.

Tuesday's expected showdown comes a month after the board voted 9 to 8 against an emergency motion to delete the lesson plan. Martha W. Wise, a board member who sponsored that motion, said that this time she would propose removing both the lesson plan and the critical analysis benchmark, while also restoring a fuller definition of science to note that its theories "while not 'believed in' through faith may be accepted or rejected on the basis of evidence."

Ms. Wise said she was unsure whether she had secured 10 votes for the emergency motion, but expressed confidence that a majority would at least call for a reconsideration of the lesson plan by the board's lawyers and a committee.

But Deborah Owens Fink, the board member who originally supported the dual study of evolution and design and has been the leading defender of the standards, said, "The lesson has been in use for two years, and certainly a hole hasn't been cut in the ozone or anything."

It's clear to me that the governor of Ohio is concerned that his state is going to gain a reputation as "anti-science" unless their "teach the controversy" policy is rescinded. With the National Academy of Sciences weighing in on the issue, any politician not already deeply committed to the Discovery Institute's position will be scrambling to rescind it as well...unless they're up for election, in which case they will probably be paying more attention to the Zogby poll results. Which means, of course, that the outcome will be almost purely political (i.e. it will have little or nothing to do with science).

The irony of all of this is that evolutionary biologists are having to make statements about how solid their own science is, when anybody in the field (indeed, anybody in any scientific field) knows that controversy is the name of the game. To me, that's the real danger in all of this. Not that scientists will be hoodwinked in any way by the IDers, nor that there will be any lasting harm done to public school students – after all, when I went to elementary school, we were all forced to recite a daily prayer first thing in the morning. No, the real danger is that, in attempting to show a "unified front," scientists will be tempted to suppress their own disagreements with current orthodoxy. Any inhibition on the free expression of doubts and disagreements in the scientific community would be harmful to science, in a way that "intelligent design theory" generally is not.

Saturday, February 11, 2006

Princeton President Defends Evolution

Apparently 2005 was the year that presidents of Ivy League universities decided to give speeches defending evolutionary biology and attacking "intelligent design theory." The president of Cornell, Hunter Rawlings III, gave a speech to the Cornell board of trustees on 25 October 2005 in which he lambasted "intelligent design theory" (full text of Rawlings' speech). Rawlings comments made international headlines, and stirred the ire of the Discovery Institute, home of "intelligent design theory."

Now comes news that Shirley M. Tilghman, president of Princeton University, delivered the 2005 Romanes Lecture at Oxford University on December 1, 2005. Her lecture was entitled “Strange Bedfellows: Science, Politics and Religion”, and addressed both evolution and intelligent design. Jeffrey Shallit has posted some excerpts from Tilghman's speech at The Panda's Thumb. The full text of president Tilghman's speech can be found here.

Here are the excerpts posted at Panda's Thumb:

“If cosmologists are deciphering the origins of the universe and our solar system in unprecedented ways, biologists are making enormous strides, thanks to the technology that was developed during the Human Genome Project, toward unlocking the origins of life on Earth. Yet here, too, science and politics have found themselves at loggerheads. It is impossible to ignore the increasing assertiveness of elements within American society who have challenged the validity of Darwin’s theory of natural selection and have lobbied for an alternative explanation, which they term “intelligent design,” to be taught in public schools alongside the principles of evolution. This is deeply disturbing, for the theory of natural selection is one of the two pillars, along with Mendel’s laws of inheritance, on which all of modern biology is built. It is virtually impossible to conduct biological research and not be struck by the power of Darwin’s theory of natural selection to shed light on the problem at hand. Time and again in the course of my career, I have encountered a mysterious finding that was explained by viewing it through the lens of evolutionary biology. The power of the theory of natural selection to illuminate natural phenomena, as well as its remarkable resilience to experimental challenge over almost 150 years, has led to its overwhelming acceptance by the scientific community.”

“Today, however, under the banner of “intelligent design,” Christian fundamentalists in the United States have launched a well-publicized assault on the theory of evolution, suggesting that the complexity and diversity of nature is not the product of random mutation and natural selection but rather of supernatural intent. Although exponents of intelligent design have been at pains to distance themselves from overtly religious interpretations of the universe, the intellectual roots of intelligent design can be traced to creationism, which holds that the natural world, including human beings in their present form, is the handiwork of a divine designer — namely, God. Biblical creationists contend that the world was created in accordance with the Book of Genesis — in six short days — while the followers of intelligent design eschew this literalism. They say that their goal is to detect empirically whether the “apparent design” in nature is genuine design, in other words, the product of an intelligent cause. They reject out of hand one of the central tenets of natural selection, namely, that biological change arises solely from selection upon random mutations over long periods of time. For those of you who are not conversant with the literature of intelligent design, the argument usually begins with Darwin himself, who said “If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.” From there, advocates such as Michael Behe, a professor of physical chemistry at Lehigh University, declare that “natural selection can only choose among systems that are already working, so the existence in nature of irreducibly complex biological systems poses a powerful challenge to Darwinian theory. We frequently observe such systems in cell organelles, in which the removal of one element would cause the whole system to cease functioning.”

“What is wrong with this view? To begin with, it reflects a fundamental misunderstanding of how evolution works. Nature is the ultimate tinkerer, constantly co-opting one molecule or process for another purpose. This is spurred on by frequent duplications in the genome, which occur at random. Mutations can accumulate in the extra copy without disrupting the pre-existing function, and those that are beneficial have the potential to become fixed in the population. In other instances, entirely new functions evolve for existing proteins. My favorite example is lactate dehydrogenase, which functions as a metabolic enzyme in the liver and kidney in one context, and as one of the proteins that makes up the transparent lens of the eye in another. In the first cellular setting, the protein has a catalytic function; in the second, a structural one.”

“A common weapon that is used to advance the “theory” of intelligent design is to posit that evolutionary biology cannot explain everything — that there remains uncertainty in the fossil record and that there is as yet no consensus on the origin or nature of the first self-replicating organisms. This, too, reflects a basic misunderstanding about how science works, for, in fact, all scientific theories, even those that are approaching 150 years of age, are works in progress. Scientists live with uncertainty all the time and are not just reconciled to it but understand that it is an integral part of scientific progress. We know that for every question we answer, there is a new one to be posed. Indeed, the very word, “theory,” is misunderstood by many who take it to mean an “idea” that has no greater or lesser merit than any other idea. The fact that Darwin’s “ideas” on natural selection have stood the test of time through keen experimental challenge does not give his theory special status in their eyes. There are also those who exploit the fact that scientists often disagree over the interpretation of specific findings or the design of experiments to argue that nothing is settled and thus anything is possible. The fact of the matter is that fierce disagreement is the stuff of scientific inquiry, and the constant give-and-take is needed to test the mettle of our ideas and sharpen our thinking. It is not, as many would claim, prima facie evidence for deep fissures in the central tenets of natural selection.”

University presidents, like Rawlings and Tilghman, have a vested interest in maintaining the integrity of science, especially at the college and university level. Yes, I know, universities started out as religious institutions, but that is generally no longer true. It is especially not true of Cornell, which was the first major university in the world to be founded without a sectarian focus. This was due primarily to the fact that Ezra Cornell was a Quaker, and therefore there could be no divinity school at his university. For those who don't know, Quakers have neither formal creeds nor divinity schools or theology programs. Several colleges were founded by Quakers, especially in the United States – Earlham and Swarthmore come to mind – but even there, Quakerism was a background "culture" but was never officially taught as a subject in theology, nor did they ever award degrees in divinity.

Since its founding Cornell has therefore had a reputation as "that godless institution in Ithaca," a reputation that was enhanced early on when its first president, Andrew Dickson White, published a monumental two-volume work on The Warfare Between Science and Theology in Christendom. White's book was immensely influential at the time of its publication, and reinforced the ascendancy of Darwinian theory in the United States.

I hope that this trend continues, and that college and university presidents everywhere will speak out against politically motivated attempts by quasi-Fundamentalist organizations like the Discovery Institute to undermine research and teaching in science. After all, there are plenty of religious colleges and universities in the United States, where Fundamentalists and their supporters can promote their views.

If religiously motivated "scientists" want to try to change the minds of their colleagues, let them do it the old-fashioned way: get out in the field (or in the lab) and do some actual empirical research, analyze the results, and submit them for publication in genuine peer-reviewed journals. If there really is anything observable in nature to back up their hypotheses, this should be no problem. And believe me, the first "intelligent design theorist" who manages to do so will easily become as famous as Darwin or Einstein...after, but not before they make such a breakthrough.